wiaed



A 2 sneets-lsheet'l. G. WIARD.

Patented Aug. 31,1880.

Mold for (Blasting Chilled Mold Boards.

A l ZSheets-Sheet 2.. G. WIARD. l Moldfor `Casting Chilled Mold' Boards.

No. 231,877. Patented A ug. 31, 1880.

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N.PEKF.RS, PHOTO-UTHOGRAPHiR. WASHINMON D c UNITED STATES PATENT OEEICEQ GEORGE WIAED,

OF BATAVIA, NEW YORK, ASSIGNOR TO THE WIARD PLOW COMPANY, OF SAME PLACE.

MOLD FOR CASTING CHILLED MOLD-BOARDS.

SPECIFICATION forming part of Letters Patent No. 231,877, dated August 31, 1880. Application led December 2, 1879.

To all whom it may concern:

Be it known that l, GEORGE VVIARD, of Batavia, in the county of Genesee and State of New York, have invented a new and useful Improvement in Molds for (lasting Chilled Mold-Boards, ot' which the following is a specilication, reference being had to the accompanying drawings.

My invention relates more particularly to the construction of the chill which `Forms one side ot' the mold in which the 1nold-board is cast, and also to the construction of' the flask or frame of the mold. i

Chills as ordinarily used in casting moldboards consist of a ilat plate of iron, which is secured to the tlask so as to form the outer side of the mold. The hot metal enters the mold at the bottom and rises in the mold until the same is tilled. The chill is subjected at the point where the liquid enters the mold to the heating' action ot' the current oi' hot molten metal, while those parts of the chill which are farther removed from the point at which the hot meta-l enters thc mold become less heated,because the metal when it reaches those parts has become considerably cooled by contact with the chill. In this manner the chill isunequally heated and becomes warped, thereby changing the formY of the mold and producing castings of unequal thickness, and eventually resulting in the cracking and nal destruction ofthe chill. The unequal heating of the chill also causes an unequal chilling or hardening of the casting, because the highlyheated portions of the chill near the point at which the metal enters do not permit the casting to cool as quickly as the less-heated portions near the extremities of the chill.

The object of my invention is to remedy these difficulties; and it consists in constructing the chill thickest at the point where the molten metal enters the mold and gradually decreasing the thickness of the chill from that point toward its extremities.

In the accompanying drawings, consisting of two sheets, Figure l is an elevation of a mold with the chill-plate removed. Fig. 2 is a vertical section in line x x, Fig. l. Fig. 3 is a section in line y y, Fig. l. Fig. 4 is an elevation of the mold with the chill-plate applied them' Fig. 5 is a section in line z e, Fig. l.

Like letters of reference refer to similar parts in the several igures.

A represents theiiask or frame of the mold, and B that portion of the mold which is composed ot' sand rammed into the ilask.

'C represents the pattern-ot' the mold-board; d, the gate or opening at which the metal en* ters the bottom of the mold, and e the passage or channel into which the metal is poured.

F is the chill-plate, provided on its upper and lower sides with stiffening-ribs g, and fitting against the open-face side ofthe flask, to which it is Jfastened by clamps h and wedgekeys i. '.lhe chill-plate is constructed thickest opposite the gate d where the molten metal enters the mold, and its thickness decreases from that point in all directions toward the extremities of the mold. For casting a mold-board of ordinary size the chill is made opposite the gate 'd about three inches thick, and its thickness is gradually reduced in all directions toward the edges ot the mold, where the chill is made about. three-quarters ot' an inch thick. The molten metal entering the mold through the gate d irst comes in contact with the thickest portion of the chill, and as the metal rises and spreads in the mold and loses a portion of its heat it comes in contact with successively-thinner portions of the chill-plate. As the capacity of the chill-plate for absorbing heat is in proportion to its thickness, the thicker portion, which is exposed to contact with the hottest metal, and the thinnerV portions, which are acted upon by the partially-cooled metal, are uniformly heated. By this means `the warping of the chill-plate and the consequent distortion of the mold, producing castings ot' unequal thickness, are preven ted7 and the castings are chilled to a uniform degree or" hardness over their entire surface.

The metallic chill-plate F prevents the air and vapors which are generated and displaced by the molten metal entering the mold from being absorbed at the front side of the mold, the surface capable of absorption being confined to that portion of the mold which is 4 formed of sand.

In order to provide a means of escape for the gases and vapors which are not absorbed by the sand7 the upper bar of the flask A is provided on its face side with narrow vertical grooves l. After the pattern is molded in the lask the grooves l are continued in the face of the sand portion of the mold to the upper edge of the mold, as clearly shown in Fig. l.

The groovesl and their continuations are preferably made about one-sixteenth part of an inch in vvidth and depth. The small size of these grooves prevents the molten metal from entering the same, as the metal has become considerably cooled when it reaches the upper edge ofthe mold. The vapors and air which are not absorbed by the sand are driven from the mold through the grooves l, thereby insuring castings which are free from air-holes.

I claim as my invention- A metallic chillplate for casting moldzo boards and similar articles7 made thickest at the point Where the molten metal enters the mold7 and made gradually decreasing in thickness toward the extremities of the mold in all directions, substantially as set forth.

GEORGE WIARD.

Witnesses F. RAMSDELL, C. W. HoUGH. 

